Power skin care appliances typically include a moving, usually oscillating, workpiece portion, such as a brush/bristle portion, also referred to as a brushhead. The brush portions gradually age, wear or become contaminated over time and with use. Further, workpieces that dispense consumable materials gradually become depleted. These gradual physical workpiece changes will result in performance decline of the appliance, either from changes in dynamic properties which produce amplitude motion differences or more directly from changes in the characteristics of the brush/bristles themselves, such as suppleness. Such brush workpieces are generally intended to be replaced when performance of the appliance no longer meets a particular standard.
Loss in performance, however, typically occurs so gradually that satisfaction with the product is also gradually reduced until the workpiece is in fact replaced. In some cases the appliance is erroneously discarded before the workpiece is replaced.
Accordingly, it is desirable that workpiece performance and the resulting experience by a user is maintained at an acceptable level until the typical time for replacement of the workpiece occurs, which typically is approximately three months.